Means for preventing the fluttering and canoeing of strip work

ABSTRACT

An illustrative embodiment of the invention prevents strip work from &#39;&#39;&#39;&#39;fluttering&#39;&#39;&#39;&#39; and &#39;&#39;&#39;&#39;canoeing&#39;&#39;&#39;&#39; by establishing spaces of static high pressure fluid on both sides of the strip. Preferably, jets of pressurized fluid form the periphery of each of the static high pressure spaces. The jets and the static pressure thus formed, push the adjacent portion of the strip work back toward an equilibrium position with an increasing force as the strip comes closer to the jets in order to restore a wellbalanced condition on both sides of the strip that eliminates fluttering and canoeing. This technique can be used in a cooling zone to heat treat the strip work, for example, in a continuous annealing furnace.

United States Patent Hiraiet al.

1451 Aug. 1, 1972 [54] MEANS FOR PREVENTING THE FLUTTERING AND CANOEINGOF STRIP WORK [72] Inventors: Masuhiko Hirai, Hiroshima; TakeoFukushima, Itsukaichi-machi, both of Japan [73] Assignee: MitsubishiJukogyo Kabushiki Kaisha, Tokyo, Japan [22] Filed: Dec. 11,1969

21 Appl. No.1 884,162

[30] Foreign Application Priority Data Dec. 14, 1968 Japan ..43/9l818[52] US. Cl ..226/97 [51] Int. Cl. ..B65h 17/32 [58] Field of Search..226/7, 92; 34/156, 160

[56] References Cited UNITED STATES PATENTS 3,448,907 6/1969 Otepka.........34/156 x 3,181,250 5/1965 Vits ..34/23 2,848,820 8/1958 Wallinetal ..226/97X Primary Examiner-Allen N. Knowles Assistant Examiner-GeneA. Church Attorney-McGlew and Toren [57] ABSTRACT An illustrativeembodiment of the invention prevents strip work from fluttering andcanoeing by establishing spaces of static high pressure fluid on bothsides of the strip. Preferably, jets of pressurized fluid form theperiphery of each of the static high pressure spaces. The jets and thestatic pressure thus 3 0111615,: Drawing Figures PATENTEDMIQ 1 I9723.680.756

F IG. 5

INVEVIURS MASl/H/KO y QKEO FUKUSH/MA A TTOR/VEYS MEANS FOR PREVENTINGTI-IE FLU'I'TERING AND CANOEING OF STRIP WORK DETAILED EXPLANATION ONTHE INVENTION The present invention relates to an improvement made inmeans for preventing the fluttering and canoeing of the strip work.

In a strip work processing line, or more particularly, a continuousannealing furnace for heat-treating strip work, the strip work goesthrough several serpentine movements in the furnace and further passesthrough a plurality of heat-treating zones that are varied intemperature. Consequently, the strip work is liable, because of theinfluence of the heat and also because of its intrinsic characteristicsfor rolling, to wave in direction normal to its surface, or in otherwords to flutter, and thereby to cause trouble in tracking and tounfavorably influence the heat treatment and the equipment used. I

In order to prevent the fluttering of the strip work as described above,a mechanical meanshave been used in which several pairs of rolls areprovided at various places in the furnace to hold the strip work fromboth sides, but this process is unsatisfactory because the surfaces ofthe strip work are liable to be damaged from contact with the rolls.

To overcome the aforesaid drawback, the present invention proposes animproved means to prevent strip fluttering without causing surfacescratches by on its surface characterized in providing two lines of airchambers to face each other with the strip work travelling between them,the openings of each of said air chambers being disposed to face thesurface of the strip work, each of such opening being divided by severalpartitions transverse to the direction of the strip work, andforming,when fluid pressure is supplied to the air respective chambers, to forma static pressure region in each partitioned opening between the stripwork, the air chamber fluid being supplied in a jet from eachpartitioned opening.

BRIEF DESCRIPTION OF THE ATTACHED DRAWINGS In the drawings showing apreferred embodiment of this invention,

FIG. 1 is a plan view showing a whole system including a partial sectionof the same,

FIG. 2 a front elevation view as seen from the line II II of FIG. 1,

FIG. 3 a sideview of FIG. 2,

FIG. 4 an enlarged section of FIG. 3, and

FIG. 5 is a sketch cited for illustration.

Now, a preferred embodiment of this invention will be explained withreference to the attached drawings, in which 1 represents two lines ofair chambers provided on both sides of the travelling strip work S andsaid air chamber 1 is divided into three spaces or volumes A, B, and C,by the partitions 2, 2 provided in direction normal to the surface ofthe strip work. The air chamber on the other side of the strip work hasthe structure, although not shown in the drawing, exactly the same asthe other. Further, the hypothetic line S, in FIG. 1 shows the stripwork travelling proximately and parallel to the air chamber 1, and thehypothetic line 8,, in FIG. 1 indicates the strip work travelling inabnormal condition close to the air chamber 1. The air chamber to.oppose the surface of the strip work as seen in FIG.

2. The spaces, A, B, and C are designed, from the functionalrequirement, so that the spaces A and C are divided to be somewhatsmaller in width, and the central spaces B is'somewhat larger in width,and each of these spaces is connected with pipe 5 to supply fluid samein pressure and in flow rate.

Next, the guide pieces 6, 6 are provided respectively in said openings4, 4 and serve to form peripheral passages for the fluid in the openings4, 4. This fluid passage makes its way through all sides of the guidepieces 6, 6 because these guide pieces 6 6 are installed in the airchamber, asshown in FIG. 4, by

means of the beams 7, 7 with hollow space around it and further they aremade smaller in size and convergent in shape like opening D. The guidepiece 6 is attached in the air chamber 1 by fixing to the air chamber 1the fixed piece 8 by bolt and such fixed piece 8 is welded to the beamfixed to the guide piece 6 by weldmg.

Because of the mechanism disclosed by this invention as described above,fluid under pressure is ejected from the opening 4 4 passing through thepassage around the guide piece 6, 6 when the fluid is supplied undersame pressure and in same flow rate into the spaces, A, B, and C in theair chamber 1 through the pipes 5, 5 from the source (not shown in thedrawing). When the strip work travels on the center line between the airchambers 1 and l as shown in FIG. I, the strip receives same thrust bythe pressure fluid ejected from the air chambers l, l on both sides, andtherefore the strip work travels in this state up and down unless thestrip work is otherwise influenced. But, if the strip work travelscloser to the air chamber on one side, as shown by the hypothetic line8,, of FIG. 1, the strip work receives on the side closer to the airchamber a greater thrust from pressure fluid jetted through the openings4, 4 than the thrust it receives on the other side that is remote fromthe air chamber. The strip work in this manner is reverted to the centerline where the thrust from both side becomes balanced. As stated in theforegoing, the strip work when coming closer to either air chamber ispushed back by the fluid pressure that is jetted from the opening 4, 4and is enabled to travel always in a well-balance condition.

Owing to the mechanical structure as described in the foregoing, thestrip work regulating means as disclosed in this invention is able toovercome the drawback commonly found in the conventional strip workregulating system as described in the following. In a case where theconventional system as shown in FIG. 5 is used, the pressure fluidflows, when the strip work comes close to the air chamber by a strongforce due to some reason or other, in direction shown by the arrows inFIG. 5. The thrust works in direction normal to the strip, and becausethe pressure fluid flows upand downwardly at an extremely high flowrate, the center F of the opening becomes close to negative pressure.The the strip work comes still closer, until at last the strip workcannot be pushed back and, in the worst case, the strip work comes tocontact the head of the opening.

However, in the strip work regulating means as disclosed by this thefluid ejected as shown by E of FIG. 4 is blown against the strip work bya given angle. Therefore the ejected fluid does not escape in upwardlyor downwardly direction and is sure on impact to the strip work and topush it back. Particularly because the fluid is ejected through thepassage around the guide piece 6 the center E comes to form a space orroom that is bounded by the air current characterizing the pres surizedfluid the, strip work and the air chamber or the guide piece 6. In thisinstance, the space has a a static pressure that helps to push back thestrip work with increasing force as it draws closer to the guide piece6. The angle of inclination of the passage for jetting fluid to beformed by the opening D is convergent in shape and the guide piece 6, isfound by the experiment made by the present inventors preferably to befrom 30 to 60. Further, because the opening D is divided in transversedirection to the strip work, when a part of the strip work comes closeto the opening as seen in the hypothetical line S II of FIG. 1, eachopening 4 gives push back force corresponding to the distance to thestrip work and can push back the strip work with good effect. 7

Furthermore, because the whole air chamber 1 in the strip workregulating system as disclosed by this invention is partitioned intoseveral spaces, A, B, C, etc., when the strip work comes close as seenin the hypothetical line 8,, of FIG. 1, the pressure fluid jetted fromthe space at the right most end increases the transverse movement of theforce to resist the strip work and the pressure within the space rises.Such increased pressure works to give thrust to the strip work withoutescaping into other spaces and thereby increasing the thrust by means ofthe partitioned spaces. Further, because the strip work often approachesto the opposite surfaces flat all over as shown by the hypothetical lineS, of FIG. 1 or in a sloped state as shown by the hypothetical line 8,,of FIG. 1, the air chamber 1 should preferably be divided into thespaces in a manner in which the spaces at both ends are somewhat smallerin dimension than the one at the center in order to achieve a goodfunctional result. This also holds true when dividing the spaces, A, B,and C further into smaller partitions.

Furthermore, this invention strip work regulating means can be used withgood result also in a cooling zone when heat-treating the strip work ina continuous annealing furnace. Because the pressurized fluid is blownagainst the strip work from the openings as stated in the foregoing, theresult of cooling can be further increased by using the cooling mediumas the pressurized fluid. This invention system can serve the doublepurpose that is, cooling and the prevention of fluttering withoutproviding any particular equipment in the cooling zone other than thecooling instrument.

Generally, the term fluttering" means the waving of the strip work asseen in the hypothetical lines S, and S of FIG. 1. This inventionsystem, however, shows a good result also in the prevention of thebowing or socalled canoeing of the strip work. Therefore, when used jn tatent s ecific tion the term fl ter'n also is to e constru ied toinclude canoemg of the strip work.

Further, the present invention shall in no way be restricted by theexample as described in the foregoing and various modifications withinthe scope as described in claim shall be included in this invention.

To summarize, the present invention proposes an improved strip materialregulating system in which air chambers are provided in manner thetravelling strip work can pass between them, each of said air chambershaving openings disposed to face or oppose to the surface of the stripwork, said opening being divided into several partitions in directtransverse to the strip work so that each of said partitions be given astatic pressure zone formed by the fluid jetted from each partition, airchamber and the strip work when the pressure fluid is supplied into eachair chamber and thereby the strip work go through heat-treatment withoutsuffering any scratch from the fluttering to the great advantage to theindustry.

I claim:

1. A device for preventing the fluttering of strip work which isdirected along a path for treatment, comprising at least one housingdefining a fluid chamber having a discharge adapted to be directedtoward the strip work for positioning and treating the strip work, thedischarge of the said fluid chamber comprising an opening elongated inthe direction of the longitudinal axis of the strip work, a plurality ofpartitions extending transversely across said housing and dividing thedischarge opening into several smaller openings, a guide piecepositioned centrally within each smaller opening and leaving an annularperipheral slot between said guide piece and the respective adjacentones of said partitions and defining an annular fluid jet dischargeopening, and a fluid pressure pipe connection to said housing forsupplying a constant pressure and flow fluid to said housing in thedirection of said discharge opening, said housing having walls boundingsaid discharge opening extending substantially parallel to the axis ofsaid fluid pressure pipe connection.

2. A device, according to claim 1, wherein at least one housingcomprises two oppositely arranged housings between which the strip workis positioned, said guide pieces comprising rectangular members withside walls arranged in spaced parallel relation to said partitions.

3. A device, according to claim 1, wherein said housing includes acentral large housing portion and an end housing portion on each side ofsaid central housing portion, each having said partitions and eachhaving a fluid pressure pipe connection.

1. A device for preventing the fluttering of strip work which isdirected along a path for treatment, comprising at least one housingdefining a fluid chamber having a discharge adapted to be directedtoward the strip work for positioning and treating the strip work, thedischarge of the said fluid chamber comprising an opening elongated inthe direction of the longitudinal axis of the strip work, a plurality ofpartitions extending transversely across said housing and dividing thedischarge opening into several smaller openings, a guide piecepositioned centrally within each smaller opening and leaving an annularperipheral slot between said guide piece and the respective adjacentones of said partitions and defining an annular fluid jet dischargeopening, and a fluid pressure pipe connection to said housing forsupplying a constant pressure and flow fluid to said housing in thedirection of said discharge opening, said housing having walls boundingsaid discharge opening extending substantially parallel to the axis ofsaid fluid pressure pipe connection.
 2. A device, according to claim 1,wherein at least one housing comprises two oppositely arranged housingsbetween which the strip work is positioned, said guide pieces comprisingrectangular members with side walls arranged in spaced parallel relationto said partitions.
 3. A device, according to claim 1, wherein saidhousing includes a central large housing portion and an end housingportion on each side of said central housing portion, each having saidpartitions and each having a fluid pressure pipe connection.